The white pine forests for which the calculations were made are almost pure white pine. There is a small percentage of understory hardwoods such as striped Maple and very young black birch, but the volume is insignificant. There's a stray hemlock here and there, which can be a little older, but agin, the contribution to the biomass total is minor. By contrast, when the white pine forests age and the stands break up, hemlock and hardwoods come back in and eventually become significant to dominant to very dominant. I'm restricting my attention to white pines at their peak.

Bob

Robert T. Leverett
Co-founder, Native Native Tree Society
Co-founder and President
Friends of Mohawk Trail State Forest
Co-founder, National Cadre

My vote for most above ground biomass in eastern US forests would be second-growth superlative sites of Liriodendron or Populus deltoides. End of October I should find myself in likely the most productive Liriodendron forest ever documented, and will make an effort to collect at least some cursory biomass data.

KoutaR wrote:I now notice I wrote "I have not found such a value". Of course, I wanted to write now instead of not: "I have now found such a value".

Will, I look forward to the maximum values for Liriodendron!

Kouta

Kouta,

Just to be on the same page, are the tonnage values based on green, air dry, or oven- dry equivalents for wood weight?

A single, "barely superlative" Liriodendron I have climbed and measured has a 10,200 pound air dry weight. There could be dozens of these per acre and perhaps 80-100 per hectare on superlative sites. Although there would be larger and smaller trees on any site, this tree as an average would only be a bit over 400 tons (non-metric) per HA with 80 trees.

That's a good question. When I made my study I used the Wood Density Database. There were several densities for each species. I am not sure anymore which one I used, I think I used the dry weight. Unfortunately, the Wood Density Database doesn't work anymore ("Page not found") and I had to search the Internet for the beech density. I found a paper called "Selected properties of European beech (Fagus sylvatica L.)" by Gryc et al. (you will find it with Google). It gives mean densities at 12% moisture from 0.737 to 0.769. Then I found 0.59 from the Encyclopedia of Life (http://eol.org/pages/1143547/overview). It does not specify if it is dry or 12% weight but I chose it because it is much lower than the values in the paper by Gryc et al.

Perhaps Joe as a forester knows the dry weight of beech wood? I guess European and American beech have about similar densities.

A further uncertainty is that my reference does not tell how large was the study plot.

All my values are metric tons.

A few days ago I started to do a comparison of the most massive tree species on Earth by using masses instead of volumes (eucalypts could be immediately after redwoods), but it was too difficult to find comparable densities as the Wood Density Database is out of function.

Quercus virginiana has one of the highest densities of any eastern tree- and get huge. At a dry weight of 62 lbs per ft3 a single large tree could weigh 155 short tons as an individual...

Tropical hardwoods- with some having huge specific gravity values- could really rack up some biomass in stem mass alone. A tropical tree one-third the wood volume of a western US conifer could have the same mass. However, my recent trip to Panama and Costa Rica revealed the largest volume trees (at least where we were sampling) were species with very light wood. So even though they had volumes of +/- 3,000 cubic feet in trunk only, the specific gravity of the species would make it equivalent to a much smaller tree with denser wood. I have no data to back this up but after many days sampling in Central America I felt biomass was not much more than the best of the s. Appalachian cove forests. Tree sizes were comparable (above buttress) and although taller on average, tree volume (and specific gravity) was not vastly different on a unit area perspective. That is just my impression of the forests I had privilege to see so by no means is it a blanket statement! However, these trees covered a larger part of the landscape than few and far between superlative cove forests of the s. Appalachians...

There is a large variation in beech wood density in different sites and papers on the Internet. I searched for papers studying biomass density values for beech forests. Which value would they use? Koprivica et al. (2010, see source #15 in message #1) states:

Assmann (1961) states that the average density of common beech timber is
560 kg/m3, while Cienciala et al. (2006) state that the density of beech stemwood is
575.5 kg/m3 while the density of brushwood amounts to 560.1 kg/m3. Furthermore, the
Intergovernmental Panel on Climate Change (IPCC 2003) mentions 580 kg/m3 as the
recommended wood density of beech trees. By using the local volume table for the whole
aboveground tree (without leaves and stumps) (Matic et al. 1963) we estimated wood density
is approximately 565 kg/m3.

They are speaking about dry weights. I calculated the mean of the four values (omitting the brushwood density as it only forms a small part of the tree) - it is 0.57. With this density the exceptional biomass value (for Izvoarele Nerei) would be 681 t/ha. I edited message #1 again.

Wow - Quercus virginiana is almost as heavy as water!

How tall was the tallest tree you measured in Central America? Beautiful photo!

I think, ecologically it makes more sense to compare masses than volumes. From the estetical point of view, it is the same if the wood is spongy Sequoiadendron wood or iron hard Eucalyptus wood.